Rheotome



(No Model.)

G. E. PRAGNELL. O

RHEOTOME.

No. 450,319. Patented Apr. 14,1891.

` NITED STATES PATENT OFFICE.

GEORGE EDWARD PRAGNELL, OF BROOKLYN, NEV YORK.

. RH EOTOM E.

S'PECIFICATION forming' part of Letters Patent No. 450,319, dated April 14, 1891.

Application filed April 12, 1890. Serial No. 847,601. (No model.)

To aZ whom it may concern:

Be it known that I, GEORGE EDWARD PRAG- NELL, of Brooklyn, in the county of Kings 'and State of New York, have invented a certain new. and useful Improvement in Rheotomes or Interrupters, of which the following is a specification.

Myimprovement in rheotomes or interrupters is especially applicable to electric bells. I will describe it in connection with an electric bell, and then point out the novel features in the claims.

In the accompanying drawings, Figure lis a front view of an electric bell provided with a rheotome or interrupter embodying myimprovement. Fig. 2 is a similar view showing certain parts in different positions. Fig. 3 is a side view of the bell and its appurtenances.

Similar letters of reference designate corresponding parts in all the figures.

A designates the bell` It is mounted upon a pillar B,which extends from a base-piece C.

D designates the clapper of the bell. It is attached to the armature e of an electro-magnet E. This electro-magnet is fastened to the base-piece, and the armature is journaled in a bracket c, extending from the base-piece O, one of the bearings for the armature being made in the'form of a screw c'. The bracket c is shown as arranged to one side of the electro-magnet, and the journals of the armature are represented as located between the ends of the piece of metal of which the armature is formed. Beyond the electro-magnet and bracketthe piece of metal of which the armature is formed has connected to it aspring F, whereby the armature will be retracted from the magnet. This spring is shown' as connected to a screw f, that passes through the pillar projecting from the basepiece, and provision is afiorded for the adjust-ment of the screw by means of nuts fitted to the screw on opposite sides of the pillar.

G' G2 designate binding-posts in which may be secured Circuit-wires leading from an electric battery. The binding-post G' is insulated from the base-piece. From the binding-post G' a wire g', insulated from the. base-piece, extends to one of the spools of the electromagnet. The circuit passes from this spool to the other spool, and from the latter a wire Q2, insulated from the base-piece, extends to lar a lever H is loosely mounted to oscillate in the same plane as the armature of the magnet oscillates. .As shown, this lever is provided with a central hub, which fits the for- Ward end of the pillar, and is secured in place upon the pillar by a washer h, arranged rearwardly of it and pressed forward by a spring h', and the head of a screw h2, which extends over the front of the hub. The spring h' causes the washer to act as a brake, which will prevent the lever from moving too freely out of any position which it may take without seriously impeding its action. The armature e is provided with a spring or strip hm, and this is located in a position to contact with that end of the lever I-I which is the nearer to the bell. This end of the lever is turned towardf'the spring or strip and armature. It is not intended that any electric communication shall occur between the lever and this spring or strip. Hence when the latter is made of metal it will be insulated from the armature or insulating material will be applied to the end of the lever contacting with it. In the present instance the strip is made in the form of a metal spring and is secured to the armature by a screw in combinationI with washers, which will insulate the strip. from the armature and the screw.

The end of the lever H which is the farther from the bell is projected toward that portion of the metal forming the armature which is beyond the fulcrums or journals of the same. In the present instance this is accomplished by providing the said end of the lever with a screw ha. This screw may be adj usted to pro- IOO cuit extends through the lever I-I to the projection or screw h, thence to the piece of metal forming the armature of the electromagnet, from the latter to the bracket c, and thence through the base-piece to the bindingpost G2.

Normally the electric Circuit is closed between the binding-posts G' G2, because when the parts of the rheotome or interrupter are not in operation the projection or screw 77,3 of the lever H contacts with the metal forming the armature e, thereby completing` the Circuit. l/Vhen a current is supplied to the binding-posts G' G2, the electro-magnet will attract the armature, and, by the movement of that portion of the metal forming the armatnre which is beyond the pivots, swing off the end of the lever H which is the farther from the bell. Thelever H Will in this movement acquire a momentum and be carried slightlyfarther than the portion of the armatnre which is opposite the screw 72,3, and owing to this the Circuit Will be broken. On the breaking of the Circuit the magnet becomes de-energized, the armature swings away from it, and thereupon the spring or strip h1,contacting with the adjacent end of the lever H, oscillates this lever back to its normal position, thereby Cansing the screw 713 to again contact With the piece of metal of which the armature is formed. The closing of the Circuit in this manner Causes a repetition of the Operations described.

By my improvement I am enabled to use a small current of electricity to better effect than with the ordinary rheotome or interrupter; and, moreover, I am able to employ a larger current without drawing an arc than is possible with a rheotome or interrupter of common form.

lt will be readily seen that the lever H Constitutes a Circuit-changer.

`Nhat I Claim as my inVent-ion, and desire to secure by Letters Patent, is-

1. The combinatiomwith a rheotome or interrupter, of an electro-magnet, an armature therefor, a strip of spring material on said armature but insulated therefrom, an electric circuit, and a lever contacting With the strip of spring material of the armature at one end and havingv an adjustable screw at the other end contacting with the metal of which the armature is formed, substantially as specified.

2. The combination,in a rheotome orinterrupter7 of an electro-magnet, an armature therefor, an electric Circuit, and a Circuitchanger consisting of a lever operated by the movement of the armature to open and close the Circuit insulated from the armature at one end and having a yielding bearing thereon and constructed at the other end to make and break electrical communication with the metal of which the armature is formed, substantially as specified.

3. The Combinatiomwith a rheotome or interrupter, of an eleCtro-magnet, an armature therefor, a strip or spring on said armature but insulated therefrom, an electric circuit, and a lever contaoting with the strip or spring of the armature at one end and contacting at the other end with the metal of which the armature is formed, substantially as specified.

GEORGE EDWARD PRAGNELL.

Witnesses:

J. J. VAIL, WM. H. H. SIsUM. 

